Almond Orchard Management Considerations for October

Keep this checklist on hand to make sure you complete all these important practices this month!

Survey for stick-tights/mummy nuts. Nuts stuck to the tree well after harvest may indicate hull rot. In certain areas, this could also be a result of high boron. If hull rot is indicated, consider revising irrigation and nitrogen management practices that may encourage hull rot next year. If more than 2 nuts per tree remain, plan to knock off and destroy mummies by February 1st to reduce navel orangeworm and brown rot.

If rust infection was heavy this year, consider a foliar zinc sulfate spray to hasten leaf fall to ensure infected leaves don’t carry over into next season. Wait until late October or early November to allow leaves time to continue making photosynthate and build up energy storage in the trees after harvest.

Watch for shot hole fruiting structuresin leaf lesions after fall rains begin. If fruiting structures producing spores are present in leaf lesions in the fall, there is a greater risk of shot hole development the following spring. Foliar zinc sulfate applied in late October or early November can also hasten leaf fall and reduce shot hole inoculum.

The black spots in the center of these shot hole lesions are the fruiting bodies.

Scout for weeds after the first fall rains. Look for late summer weeds that escaped this year’s control and winter annual weeds that are just emerging. UC IPM has a late fall weed survey form that can help. The UC Weed ID Tool may also help.

Consider a fall nutrient spray. Check hull boron and leaf zinc analyses results to help determine if a foliar spray of either or both nutrients is needed.

Planting a cover crop to improve soil, provide pollen to bees, and/or reduce runoff? Get it in the ground by the end of October for best stand establishment.